Compositions containing fluorine substituted olefins and methods and systems using same

ABSTRACT

Disclosed are the use of fluorine substituted olefins, including tetra- and penta-fluoropropenes, in a variety of applications, including in methods of depositing catalyst on a solid support, methods of sterilizing articles, cleaning methods and compositions, methods of applying medicaments, fire extinguishing/suppression compositions and methods, flavor formulations, fragrance formulations and inflating agents.

RELATED APPLICATIONS

The present application is related to and claims the priority benefit ofeach of the following United States Patent Applications: U.S.application Ser. No. 10/837,525, filed Apr. 29, 2004 (now U.S. Pat. No.7,279,451), which in turn is a continuation in part of each of U.S.Application Ser. No. 10/694,273 (now U.S. Pat. No. 7,534,366) and Ser.No. 10/694,272 (now U.S. Pat. No. 7,230,146), each of which was filedOct. 27, 2003, and each of which in turn is related to and claims thepriority benefit of U.S. Provisional Applications 60/421,263 and60/421,435, each of which was filed on Oct. 25, 2002. The disclosure ofeach of the patent applications and patents identified in the precedingsentence is incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to compositions having utility in numerousapplications, including particularly refrigeration systems, and tomethods and systems utilizing such compositions. In preferred aspects,the present invention is directed to refrigerant compositions comprisingat least one multi-fluorinated olefin of the present invention.

BACKGROUND OF THE INVENTION

Fluorocarbon based fluids have found widespread use in many commercialand industrial applications. For example, fluorocarbon based fluids arefrequently used as a working fluid in systems such as air conditioning,heat pump and refrigeration applications. The vapor compression cycle isone of the most commonly used type methods to accomplish cooling orheating in a refrigeration system. The vapor compression cycle usuallyinvolves the phase change of the refrigerant from the liquid to thevapor phase through heat absorption at a relatively low pressure andthen from the vapor to the liquid phase through heat removal at arelatively low pressure and temperature, compressing the vapor to arelatively elevated pressure, condensing the vapor to the liquid phasethrough heat removal at this relatively elevated pressure andtemperature, and then reducing the pressure to start the cycle overagain.

While the primary purpose of refrigeration is to remove heat from anobject or other fluid at a relatively low temperature, the primarypurpose of a heat pump is to add heat at a higher temperature relativeto the environment.

Certain fluorocarbons have been a preferred component in many heatexchange fluids, such as refrigerants, for many years in manyapplications. For, example, fluoroalkanes, such as chlorofluoromethaneand chlorofluoroethane derivatives, have gained widespread use asrefrigerants in applications including air conditioning and heat pumpapplications owing to their unique combination of chemical and physicalproperties. Many of the refrigerants commonly utilized in vaporcompression systems are either single components fluids or azeotropicmixtures.

Concern has increased in recent years about potential damage to theearth's atmosphere and climate, and certain chlorine-based compoundshave been identified as particularly problematic in this regard. The useof chlorine-containing compositions (such as chlorofluorocarbons (CFCs),hydrochlorofluorocarbons (HCFCs) and the like) as refrigerants inair-conditioning and refrigeration systems has become disfavored becauseof the ozone-depleting properties associated with many of suchcompounds. There has thus been an increasing need for new fluorocarbonand hydrofluorocarbon compounds and compositions that offer alternativesfor refrigeration and heat pump applications. For example, it has becomedesirable to retrofit chlorine-containing refrigeration systems byreplacing chlorine-containing refrigerants with non-chlorine-containingrefrigerant compounds that will not deplete the ozone layer, such ashydrofluorocarbons (HFCs).

It is generally considered important, however, that any potentialsubstitute refrigerant must also possess those properties present inmany of the most widely used fluids, such as excellent heat transferproperties, chemical stability, low- or no-toxicity, non-flammabilityand lubricant compatibility, among others.

Applicants have come to appreciate that lubricant compatibility is ofparticular importance in many of applications. More particularly, it ishighly desirably for refrigeration fluids to be compatible with thelubricant utilized in the compressor unit, used in most refrigerationsystems. Unfortunately, many non-chlorine-containing refrigerationfluids, including HFCs, are relatively insoluble and/or immiscible inthe types of lubricants used traditionally with CFC's and HFCs,including, for example, mineral oils, alkylbenzenes orpoly(alpha-olefins). In order for a refrigeration fluid-lubricantcombination to work at a desirable level of efficiently within acompression refrigeration, air-conditioning and/or heat pump system, thelubricant should be sufficiently soluble in the refrigeration liquidover a wide range of operating temperatures. Such solubility lowers theviscosity of the lubricant and allows it to flow more easily throughoutthe system. In the absence of such solubility, lubricants tend to becomelodged in the coils of the evaporator of the refrigeration,air-conditioning or heat pump system, as well as other parts of thesystem, and thus reduce the system efficiency.

With regard to efficiency in use, it is important to note that a loss inrefrigerant thermodynamic performance or energy efficiency may havesecondary environmental impacts through increased fossil fuel usagearising from an increased demand for electrical energy.

Furthermore, it is generally considered desirably for CFC refrigerantsubstitutes to be effective without major engineering changes toconventional vapor compression technology currently used with CFCrefrigerants.

Flammability is another important property for many applications. Thatis, it is considered either important or essential in many applications,including particularly in heat transfer applications, to usecompositions, which are non-flammable. Thus, it is frequently beneficialto use in such compositions compounds, which are nonflammable. As usedherein, the term “nonflammable” refers to compounds or compositions,which are determined to be nonflammable as determined in accordance withASTM standard E-681, dated 2002, which is incorporated herein byreference. Unfortunately, many HFCs, which might otherwise be desirablefor used in refrigerant compositions are not nonflammable. For example,the fluoroalkane difluoroethane (HFC-152a) and the fluoroalkene1,1,1-trifluoropropene (HFO-1243zf) are each flammable and therefore notviable for use in many applications.

Higher fluoroalkenes, that is fluorine-substituted alkenes having atleast five carbon atoms, have been suggested for use as refrigerants.U.S. Pat. No. 4,788,352—Smutny is directed to production of fluorinatedC₅ to C₈ compounds having at least some degree of unsaturation. TheSmutny patent identifies such higher olefins as being known to haveutility as refrigerants, pesticides, dielectric fluids, heat transferfluids, solvents, and intermediates in various chemical reactions. (Seecolumn 1, lines 11-22).

While the fluorinated olefins described in Smutny may have some level ofeffectiveness in heat transfer applications, it is believed that suchcompounds may also have certain disadvantages. For example, some ofthese compounds may tend to attack substrates, particularlygeneral-purpose plastics such as acrylic resins and ABS resins.Furthermore, the higher olefinic compounds described in Smutny may alsobe undesirable in certain applications because of the potential level oftoxicity of such compounds which may arise as a result of pesticideactivity noted in Smutny. Also, such compounds may have a boiling point,which is too high to make them useful as a refrigerant in certainapplications.

Bromofluoromethane and bromochlorofluoromethane derivatives,particularly bromotrifluoromethane (Halon 1301) andbromochlorodifluoromethane (Halon 1211) have gained widespread use asfire extinguishing agents in enclosed areas such as airplane cabins andcomputer rooms. However, the use of various halons is being phased outdue to their high ozone depletion. Moreover, as halons are frequentlyused in areas where humans are present, suitable replacements must alsobe safe to humans at concentrations necessary to suppress or extinguishfire.

Applicants have thus come to appreciate a need for compositions, andparticularly heat transfer compositions, fire extinguishing/suppressioncompositions, blowing agents, solvent compositions, and compatabilizingagents, that are potentially useful in numerous applications, includingvapor compression heating and cooling systems and methods, whileavoiding one or more of the disadvantages noted above.

SUMMARY

Applicants have found that the above-noted need, and other needs, can besatisfied by compositions comprising one or more C3 or C4 fluoroalkenes,preferably compounds having Formula I as follows:XCF_(z)R_(3-z)  (I)where X is a C₂ or a C₃ unsaturated, substituted or unsubstituted, alkylradical, each R is independently Cl, F, Br, I or H, and z is 1 to 3.Highly preferred among the compounds of Formula I are the cis- andtrans-isomers of 1,3,3,3-tetrafluoropropene (HFO-1234ze)

The present invention provides also methods and systems which utilizethe compositions of the present invention, including methods and systemsfor heat transfer, foam blowing, solvating, flavor and fragranceextraction and/or delivery, and aerosol generation.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The Compositions

The present invention is directed to compositions comprising at leastone fluoroalkene containing from 3 to 4 carbon atoms, preferably threecarbon atoms, and at least one carbon-carbon double bond. Thefluoroalkene compounds of the present invention are sometimes referredto herein for the purpose of convenience as hydrofluoro-olefins or“HFOs” if they contain at least one hydrogen. Although it iscontemplated that the HFOs of the present invention may contain twocarbon-carbon double bonds, such compounds at the present time are notconsidered to be preferred.

As mentioned above, the present compositions comprise one or morecompounds in accordance with Formula I. In preferred embodiments, thecompositions include compounds of Formula II below:

where each R is independently Cl, F, Br, I or H

R′ is (CR₂)_(n)Y,

Y is CRF₂

and n is 0 or 1.

In highly preferred embodiments, Y is CF₃, n is 0 and at least one ofthe remaining Rs is F.

Applicants believe that, in general, the compounds of the aboveidentified Formulas I and II are generally effective and exhibit utilityin refrigerant compositions, blowing agent compositions,compatibilizers, aerosols, propellants, fragrances, flavor formulations,and solvent compositions of the present invention. However, applicantshave surprisingly and unexpectedly found that certain of the compoundshaving a structure in accordance with the formulas described aboveexhibit a highly desirable low level of toxicity compared to other ofsuch compounds. As can be readily appreciated, this discovery is ofpotentially enormous advantage and benefit for the formulation of notonly refrigerant compositions, but also any and all compositions, whichwould otherwise contain relatively toxic compounds satisfying theformulas described above. More particularly, applicants believe that arelatively low toxicity level is associated with compounds of FormulaII, preferably wherein Y is CF₃, wherein at least one R on theunsaturated terminal carbon is H, and at least one of the remaining Rsis F. Applicants believe also that all structural, geometric andstereoisomers of such compounds are effective and of beneficially lowtoxicity.

It is even more preferred that the compounds of the present inventionare the tetrafluoropropene and pentafluorpropene compounds in which theunsaturated terminal carbon has not more than one F substituent,specifically: 1,3,3,3-tetrafluoropropene (HFO-1234ze);2,3,3,3-tetrafluoropropene (HFO-1234yf); and 1,2,3,3,3-pentafluorpropene(HFO-1225ye), and any and all stereoisomers of each of these. Applicanthas discovered that such compounds have a very low acute toxicity level,as measured by inhalation exposure to mice and rats.

In highly preferred embodiments, especially embodiments comprising thelow toxicity compounds described above, n is zero. In certain highlypreferred embodiments the compositions of the present invention compriseone or more tetrafluoropropenes. The term “HFO-1234” is used herein torefer to all tetrafluoropropenes. Among the tetrafluoropropenes, bothcis- and trans-1,3,3,3-tetrafluoropropene (HFO-1234ze) are particularlypreferred. The term HFO-1234ze is used herein generically to refer to1,3,3,3-tetrafluoropropene, independent of whether it is the cis- ortrans-form. The terms “cisHFO-1234ze” and “transHFO-1234ze” are usedherein to describe the cis- and trans-forms of1,3,3,3-tetrafluoropropene respectively. The term “HFO-1234ze” thereforeincludes within its scope cisHFO-1234ze, transHFO-1234ze, and allcombinations and mixtures of these.

Although the properties of cisHFO-1234ze and transHFO-1234ze differ inat least some respects, it is contemplated that each of these compoundsis adaptable for use, either alone or together with other compoundsincluding its stereoisomer, in connection with each of the applications,methods and systems described herein. For example, while transHFO-1234zemay be preferred for use in certain refrigeration systems because of itsrelatively low boiling point (−19° C.), it is nevertheless contemplatedthat cisHFO-1234ze, with a boiling point of +9° C., also has utility incertain refrigeration systems of the present invention. Accordingly, itis to be understood that the terms “HFO-1234ze” and1,3,3,3-tetrafluoropropene refer to both stereo isomers, and the use ofthis term is intended to indicate that each of the cis- and trans-formsapplies and/or is useful for the stated purpose unless otherwiseindicated.

HFO-1234 compounds are known materials and are listed in ChemicalAbstracts databases. The production of fluoropropenes such as CF₃CH═CH₂by catalytic vapor phase fluorination of various saturated andunsaturated halogen-containing C₃ compounds is described in U.S. Pat.Nos. 2,889,379; 4,798,818 and 4,465,786, each of which is incorporatedherein by reference. EP 974,571, also incorporated herein by reference,discloses the preparation of 1,1,1,3-tetrafluoropropene by contacting1,1,1,3,3-pentafluoropropane (HFC-245fa) in the vapor phase with achromium-based catalyst at elevated temperature, or in the liquid phasewith an alcoholic solution of KOH, NaOH, Ca(OH)₂ or Mg(OH)₂. Inaddition, methods for producing compounds in accordance with the presentinvention are described generally in connection with pending UnitedStates Patent Application entitled “Process for ProducingFluoropropenes”U.S. Application No. 13/226,019, now Pat. No. 8,247,624),which is also incorporated herein by reference.

The present compositions, particularly those comprising HFO-1234ze, arebelieved to possess properties that are advantageous for a number ofimportant reasons. For example, applicants believe, based at least inpart on mathematical modeling, that the fluoroolefins of the presentinvention will not have a substantial negative affect on atmosphericchemistry, being negligible contributors to ozone depletion incomparison to some other halogenated species. The preferred compositionsof the present invention thus have the advantage of not contributingsubstantially to ozone depletion. The preferred compositions also do notcontribute substantially to global warming compared to many of thehydrofluoroalkanes presently in use.

In certain preferred forms, compositions of the present invention have aGlobal Warming Potential (GWP) of not greater than about 1000, morepreferably not greater than about 500, and even more preferably notgreater than about 150. In certain embodiments, the GWP of the presentcompositions is not greater than about 100 and even more preferably notgreater than about 75. As used herein, “GWP” is measured relative tothat of carbon dioxide and over a 100-year time horizon, as defined in“The Scientific Assessment of Ozone Depletion, 2002, a report of theWorld Meteorological Association's Global Ozone Research and MonitoringProject,” which is incorporated herein by reference.

In certain preferred forms, the present compositions also preferablyhave an Ozone Depletion Potential (ODP) of not greater than 0.05, morepreferably not greater than 0.02 and even more preferably about zero. Asused herein, “ODP” is as defined in “The Scientific Assessment of OzoneDepletion, 2002, A report of the World Meteorological Association'sGlobal Ozone Research and Monitoring Project,” which is incorporatedherein by reference.

The amount of the Formula I compounds, particularly HFO-1234, containedin the present compositions can vary widely, depending the particularapplication, and compositions containing more than trace amounts andless than 100% of the compound are within broad the scope of the presentinvention. Moreover, the compositions of the present invention can beazeotropic, azeotrope-like or non-azeotropic. In preferred embodiments,the present compositions comprise HFO-1234, preferably HFO-1234ze, inamounts from about 5% by weight to about 99% by weight, and even morepreferably from about 5% to about 95%. Many additional compounds may beincluded in the present compositions, and the presence of all suchcompounds is within the broad scope of the invention. In certainpreferred embodiments, the present compositions include, in addition toHFO-1234ze, one or more of the following:

Difluoromethane (HFC-32)

Pentafluoroethane (HFC-125)

1,1,2,2-tetrafluoroethane (HFC-134)

1,1,1,2-Tetrafluoroethane (HFC-134a)

Difluoroethane (HFC-152a)

1,1,1,2,3,3,3-Heptafluoropropane (HFC-227ea)

1,1,1,3,3,3-hexafluoropropane (HFC-236fa)

1,1,1,3,3-pentafluoropropane (HFC-245fa)

1,1,1,3,3-pentafluorobutane (HFC-365mfc)

water

CO₂

The relative amount of any of the above noted components, as well as anyadditional components which may be included in present compositions, canvary widely within the general broad scope of the present inventionaccording to the particular application for the composition, and allsuch relative amounts are considered to be within the scope hereof.

Heat Transfer Compositions

Although it is contemplated that the compositions of the presentinvention may include the compounds of the present invention in widelyranging amounts, it is generally preferred that refrigerant compositionsof the present invention comprise compound(s) in accordance with FormulaI, more preferably in accordance with Formula II, and even morepreferably HFO-1234ze, in an amount that is at least about 50% byweight, and even more preferably at least about 70% by weight, of thecomposition. In many embodiments, it is preferred that the heat transfercompositions of the present invention comprise transHFO-1234ze. Incertain preferred embodiments, the heat transfer compositions of thepresent invention comprise a combination of cisHFO-1234ze andtransHFO1234ze in a cis:trans weight ratio of from about 1:99 to about10:99, more preferably from about 1:99 to about 5:95, and even morepreferably from about 1:99 to about 3:97.

The compositions of the present invention may include other componentsfor the purpose of enhancing or providing certain functionality to thecomposition, or in some cases to reduce the cost of the composition. Forexample, refrigerant compositions according to the present invention,especially those used in vapor compression systems, include a lubricant,generally in amounts of from about 30 to about 50 percent by weight ofthe composition. Furthermore, the present compositions may also includea compatibilizer, such as propane, for the purpose of aidingcompatibility and/or solubility of the lubricant. Such compatibilizers,including propane, butanes and pentanes, are preferably present inamounts of from about 0.5 to about 5 percent by weight of thecomposition. Combinations of surfactants and solubilizing agents mayalso be added to the present compositions to aid oil solubility, asdisclosed by U.S. Pat. No. 6,516,837, the disclosure of which isincorporated by reference. Commonly used refrigeration lubricants suchas Polyol Esters (POEs) and Poly Alkylene Glycols (PAGs), silicone oil,mineral oil, alkyl benzenes (ABs) and poly(alpha-olefin) (PAO) that areused in refrigeration machinery with hydrofluorocarbon (HFC)refrigerants may be used with the refrigerant compositions of thepresent invention.

Many existing refrigeration systems are currently adapted for use inconnection with existing refrigerants, and the compositions of thepresent invention are believed to be adaptable for use in many of suchsystems, either with or without system modification. In manyapplications the compositions of the present invention may provide anadvantage as a replacement in systems, which are currently based onrefrigerants having a relatively high capacity. Furthermore, inembodiments where it is desired to use a lower capacity refrigerantcomposition of the present invention, for reasons of cost for example,to replace a refrigerant of higher capacity, such embodiments of thepresent compositions provide a potential advantage. Thus, It ispreferred in certain embodiments to use compositions of the presentinvention, particularly compositions comprising a substantial proportionof, and in some embodiments consisting essentially of transHFO-1234ze,as a replacement for existing refrigerants, such as HFC-134a. In certainapplications, the refrigerants of the present invention potentiallypermit the beneficial use of larger displacement compressors, therebyresulting in better energy efficiency than other refrigerants, such asHFC-134a. Therefore the refrigerant compositions of the presentinvention, particularly compositions comprising transHFP-1234ze, providethe possibility of achieving a competitive advantage on an energy basisfor refrigerant replacement applications.

It is contemplated that the compositions of the present, includingparticularly those comprising HFO-1234ze, also have advantage (either inoriginal systems or when used as a replacement for refrigerants such asR-12 and R-500), in chillers typically used in connection withcommercial air conditioning systems. In certain of such embodiments itis preferred to including in the present HFO-1234ze compositions fromabout 0.5 to about 5% of a flammability suppressant, such as CF3I.

The present methods, systems and compositions are thus adaptable for usein connection with automotive air conditioning systems and devices,commercial refrigeration systems and devices, chillers, residentialrefrigerator and freezers, general air conditioning systems, heat pumps,and the like.

Blowing Agents, Foams and Foamable Compostions

Blowing agents may also comprise or constitute one or more of thepresent compositions. As mentioned above, the compositions of thepresent invention may include the compounds of the present invention inwidely ranging amounts. It is generally preferred, however, that forpreferred compositions for use as blowing agents in accordance with thepresent invention, compound(s) in accordance with Formula I, and evenmore preferably Formula II, are present in an amount that is at leastabout 5% by weight, and even more preferably at least about 15% byweight, of the composition. In certain preferred embodiments, theblowing agent compositions of the present invention and include, inaddition to HFO-1234 (preferably HFO-1234ze) one or more of thefollowing components as a co-blowing agent, filler, vapor pressuremodifier, or for any other purpose:

Difluoromethane (HFC-32)

Pentafluoroethane (HFC-125)

1,1,2,2-tetrafluoroethane (HFC-134)

1,1,1,2-Tetrafluoroethane (HFC-134a)

Difluoroethane (HFC-152a)

1,1,1,2,3,3,3-Heptafluoropropane (HFC-227ea)

1,1,1,3,3,3-hexafluoropropane (HFC-236fa)

1,1,1,3,3-pentafluoropropane (HFC-245fa)

1,1,1,3,3-pentafluorobutane (HFC-365mfc)

water

CO₂

it is contemplated that the blowing agent compositions of the presentinvention may comprise cisHFO-1234ze, transHFO1234ze or combinationsthereof. In certain preferred embodiments, the blowing agent compositionof the present invention comprise his a combination of cisHFO-1234ze andtransHFO1234ze in a cis:trans weight ratio of from about 1:99 to about10:99, and even more preferably from about 1:99 to about 5:95.

In other embodiments, the invention provides foamable compositions, andpreferably polyurethane, polyisocyanurate and extruded thermoplasticfoam compositions, prepared using the compositions of the presentinvention. In such foam embodiments, one or more of the presentcompositions are included as or part of a blowing agent in a foamablecomposition, which composition preferably includes one or moreadditional components capable of reacting and/or foaming under theproper conditions to form a foam or cellular structure, as is well knownin the art. The invention also relates to foam, and preferably closedcell foam, prepared from a polymer foam formulation containing a blowingagent comprising the compositions of the invention. In yet otherembodiments, the invention provides foamable compositions comprisingthermoplastic or polyolefin foams, such as polystyrene (PS),polyethylene (PE), polypropylene (PP) and polyethyleneterpthalate (PET)foams, preferably low-density foams.

In certain preferred embodiments, dispersing agents, cell stabilizers,surfactants and other additives may also be incorporated into theblowing agent compositions of the present invention. Surfactants areoptionally but preferably added to serve as cell stabilizers. Somerepresentative materials are sold under the names of DC-193, B-8404, andL-5340 which are, generally, polysiloxane polyoxyalkylene blockco-polymers such as those disclosed in U.S. Pat. Nos. 2,834,748,2,917,480, and 2,846,458, each of which is incorporated herein byreference. Other optional additives for the blowing agent mixture mayinclude flame retardants such as tri(2-chloroethyl)phosphate,tri(2-chloropropyl)phosphate, tri(2,3-dibromopropyl)-phosphate,tri(1,3-dichloropropyl) phosphate, diammonium phosphate, varioushalogenated aromatic compounds, antimony oxide, aluminum trihydrate,polyvinyl chloride, and the like.

Propellant and Aerosol Compositions

In another aspect, the present invention provides propellantcompositions comprising or consisting essentially of a composition ofthe present invention, such propellant composition preferably being asprayable composition. The propellant compositions of the presentinvention preferably comprise a material to be sprayed and a propellantcomprising, consisting essentially of, or consisting of a composition inaccordance with the present invention. Inert ingredients, solvents, andother materials may also be present in the sprayable mixture.Preferably, the sprayable composition is an aerosol. Suitable materialsto be sprayed include, without limitation, cosmetic materials such asdeodorants, perfumes, hair sprays, cleansers, and polishing agents aswell as medicinal materials such as anti-asthma components,anti-halitosis components and any other medication or the like,including preferably any other medicament or agent intended to beinhaled. The medicament or other therapeutic agent is preferably presentin the composition in a therapeutic amount, with a substantial portionof the balance of the composition comprising a compound of Formula I ofthe present invention, preferably HFO-1234, and even more preferablyHFO-1234ze.

Aerosol products for industrial, consumer or medical use typicallycontain one or more propellants along with one or more activeingredients, inert ingredients or solvents. The propellant provides theforce that expels the product in aerosolized form. While some aerosolproducts are propelled with compressed gases like carbon dioxide,nitrogen, nitrous oxide and even air, most commercial aerosols useliquefied gas propellants. The most commonly used liquefied gaspropellants are hydrocarbons such as butane, isobutane, and propane.Dimethyl ether and HFC-152a (1,1-difluoroethane) are also used, eitheralone or in blends with the hydrocarbon propellants. Unfortunately, allof these liquefied gas propellants are highly flammable and theirincorporation into aerosol formulations will often result in flammableaerosol products.

Applicants have come to appreciate the continuing need for nonflammable,liquefied gas propellants with which to formulate aerosol products. Thepresent invention provides compositions of the present invention,particularly and preferably compositions comprising HFO-1234, and evenmore preferably HFO-1234ze, for use in certain industrial aerosolproducts, including for example spray cleaners, lubricants, and thelike, and in medicinal aerosols, including for example to delivermedications to the lungs or mucosal membranes. Examples of this includesmetered dose inhalers (MDIs) for the treatment of asthma and otherchronic obstructive pulmonary diseases and for delivery of medicamentsto accessible mucous membranes or intranasally. The present inventionthus includes methods for treating ailments, diseases and similar healthrelated problems of an organism (such as a human or animal) comprisingapplying a composition of the present invention containing a medicamentor other therapeutic component to the organism in need of treatment. Incertain preferred embodiments, the step of applying the presentcomposition comprises providing a MDI containing the composition of thepresent invention (for example, introducing the composition into theMDI) and then discharging the present composition from the MDI.

The compositions of the present invention, particularly compositionscomprising or consisting essentially of HFO-1234ze, are capable ofproviding nonflammable, liquefied gas propellant and aerosols that donot contribute substantially to global warming. The present compositionscan be used to formulate a variety of industrial aerosols or othersprayable compositions such as contact cleaners, dusters, lubricantsprays, and the like, and consumer aerosols such as personal careproducts, household products and automotive products. HFO-1234ze isparticularly preferred for use as an important component of propellantcompositions for in medicinal aerosols such as metered dose inhalers.The medicinal aerosol and/or propellant and/or sprayable compositions ofthe present invention in many applications include, in addition tocompound of formula (I) or (II) (preferably HFO-1234ze), a medicamentsuch as a beta-agonist, a corticosteroid or other medicament, and,optionally, other ingredients, such as surfactants, solvents, otherpropellants, flavorants and other excipients. The compositions of thepresent invention, unlike many compositions previously used in theseapplications, have good environmental properties and are not consideredto be potential contributors to global warming. The present compositionstherefore provide in certain preferred embodiments substantiallynonflammable, liquefied gas propellants having very low Global Warmingpotentials.

Flavorants and Fragrances

The compositions of the present invention also provide advantage whenused as part of, and in particular as a carrier for, flavor formulationsand fragrance formulations. The suitability of the present compositionsfor this purpose is demonstrated by a test procedure in which 0.39 gramsof Jasmone were put into a heavy walled glass tube. 1.73 grams ofR-1234ze were added to the glass tube. The tube was then frozen andsealed. Upon thawing the tube, it was found that the mixture had oneliquid phase. The solution contained 20 wt. % Jasome and 80 wt. %R-1234ze, thus establishing its favorable use as a carrier or part ofdelivery system for flavor formulations, in aerosol and otherformulations. It also establishes its potential as an extractant offragrances, including from plant matter.

Methods and Systems

The compositions of the present invention are useful in connection withnumerous methods and systems, including as heat transfer fluids inmethods and systems for transferring heat, such as refrigerants used inrefrigeration, air conditioning and heat pump systems. The presentcompositions are also advantageous for in use in systems and methods ofgenerating aerosols, preferably comprising or consisting of the aerosolpropellant in such systems and methods. Methods of forming foams andmethods of extinguishing and suppressing fire are also included incertain aspects of the present invention. The present invention alsoprovides in certain aspects methods of removing residue from articles inwhich the present compositions are used as solvent compositions in suchmethods and systems.

Heat Transfer Methods

The preferred heat transfer methods generally comprise providing acomposition of the present invention and causing heat to be transferredto or from the composition changing the phase of the composition. Forexample, the present methods provide cooling by absorbing heat from afluid or article, preferably by evaporating the present refrigerantcomposition in the vicinity of the body or fluid to be cooled to producevapor comprising the present composition. Preferably the methods includethe further step of compressing the refrigerant vapor, usually with acompressor or similar equipment to produce vapor of the presentcomposition at a relatively elevated pressure. Generally, the step ofcompressing the vapor results in the addition of heat to the vapor, thuscausing an increase in the temperature of the relatively high-pressurevapor. Preferably, the present methods include removing from thisrelatively high temperature, high pressure vapor at least a portion ofthe heat added by the evaporation and compression steps. The heatremoval step preferably includes condensing the high temperature,high-pressure vapor while the vapor is in a relatively high-pressurecondition to produce a relatively high-pressure liquid comprising acomposition of the present invention. This relatively high-pressureliquid preferably then undergoes a nominally isoenthalpic reduction inpressure to produce a relatively low temperature, low-pressure liquid.In such embodiments, it is this reduced temperature refrigerant liquidwhich is then vaporized by heat transferred from the body or fluid to becooled.

In another process embodiment of the invention, the compositions of theinvention may be used in a method for producing heating which comprisescondensing a refrigerant comprising the compositions in the vicinity ofa liquid or body to be heated. Such methods, as mentioned hereinbefore,frequently are reverse cycles to the refrigeration cycle describedabove.

Foam Blowing Methods

One embodiment of the present invention relates to methods of formingfoams, and preferably polyurethane and polyisocyanurate foams. Themethods generally comprise providing a blowing agent composition of thepresent inventions, adding (directly or indirectly) the blowing agentcomposition to a foamable composition, and reacting the foamablecomposition under the conditions effective to form a foam or cellularstructure, as is well known in the art. Any of the methods well known inthe art, such as those described in “Polyurethanes Chemistry andTechnology,” Volumes I and II, Saunders and Frisch, 1962, John Wiley andSons, New York, N.Y., which is incorporated herein by reference, may beused or adapted for use in accordance with the foam embodiments of thepresent invention. In general, such preferred methods comprise preparingpolyurethane or polyisocyanurate foams by combining an isocyanate, apolyol or mixture of polyols, a blowing agent or mixture of blowingagents comprising one or more of the present compositions, and othermaterials such as catalysts, surfactants, and optionally, flameretardants, colorants, or other additives.

It is convenient in many applications to provide the components forpolyurethane or polyisocyanurate foams in pre-blended formulations. Mosttypically, the foam formulation is pre-blended into two components. Theisocyanate and optionally certain surfactants and blowing agentscomprise the first component, commonly referred to as the “A” component.The polyol or polyol mixture, surfactant, catalysts, blowing agents,flame retardant, and other isocyanate reactive components comprise thesecond component, commonly referred to as the “B” component.Accordingly, polyurethane or polyisocyanurate foams are readily preparedby bringing together the A and B side components either by hand mix forsmall preparations and, preferably, machine mix techniques to formblocks, slabs, laminates, pour-in-place panels and other items, sprayapplied foams, froths, and the like. Optionally, other ingredients suchas fire retardants, colorants, auxiliary blowing agents, and even otherpolyols can be added as a third stream to the mix head or reaction site.Most preferably, however, they are all incorporated into one B-componentas described above.

It is also possible to produce thermoplastic foams using thecompositions of the invention. For example, conventional polystyrene andpolyethylene formulations may be combined with the compositions in aconventional manner to produce rigid foams.

Cleaning Methods

The present invention also provides methods of removing containmentsfrom a product, part, component, substrate, or any other article orportion thereof by applying to the article a composition of the presentinvention. For the purposes of convenience, the term “article” is usedherein to refer to all such products, parts, components, substrates, andthe like and is further intended to refer to any surface or portionthereof. Furthermore, the term “contaminant” is intended to refer to anyunwanted material or substance present on the article, even if suchsubstance is placed on the article intentionally. For example, in themanufacture of semiconductor devices it is common to deposit aphotoresist material onto a substrate to form a mask for the etchingoperation and to subsequently remove the photoresist material from thesubstrate. The term “contaminant” as used herein is intended to coverand encompass such a photo resist material.

Preferred methods of the present invention comprise applying the presentcomposition to the article. Although it is contemplated that numerousand varied cleaning techniques can employ the compositions of thepresent invention to good advantage, it is considered to be particularlyadvantageous to use the present compositions in connection withsupercritical cleaning techniques. Supercritical cleaning is disclosedin U.S. Pat. No. 6,589,355, which is assigned to the assignee of thepresent invention and incorporated herein by reference. Forsupercritical cleaning applications, is preferred in certain embodimentsto include in the present cleaning compositions, in addition to theHFO-1234 (preferably HFO-1234ze), one or more additional components,such as CO₂ and other additional components known for use in connectionwith supercritical cleaning applications. It may also be possible anddesirable in certain embodiments to use the present cleaningcompositions in connection with particular vapor degreasing and solventcleaning methods.

Flammability Reduction Methods

According to certain other preferred embodiments, the present inventionprovides methods for reducing the flammability of fluids, said methodscomprising adding a compound or composition of the present invention tosaid fluid. The flammability associated with any of a wide range ofotherwise flammable fluids may be reduced according to the presentinvention. For example, the flammability associated with fluids such asethylene oxide, flammable hydrofluorocarbons and hydrocarbons,including: HFC-152a, 1,1,1-trifluoroethane (HFC-143a), difluoromethane(HFC-32), propane, hexane, octane, and the like can be reduced accordingto the present invention. For the purposes of the present invention, aflammable fluid may be any fluid exhibiting flammability ranges in airas measured via any standard conventional test method, such as ASTME-681, and the like.

Any suitable amounts of the present compounds or compositions may beadded to reduce flammability of a fluid according to the presentinvention. As will be recognized by those of skill in the art, theamount added will depend, at least in part, on the degree to which thesubject fluid is flammable and the degree to which it is desired toreduce the flammability thereof. In certain preferred embodiments, theamount of compound or composition added to the flammable fluid iseffective to render the resulting fluid substantially non-flammable.

Flame Suppression Methods

The present invention further provides methods of suppressing a flame,said methods comprising contacting a flame with a fluid comprising acompound or composition of the present invention. Any suitable methodsfor contacting the flame with the present composition may be used. Forexample, a composition of the present invention may be sprayed, poured,and the like onto the flame, or at least a portion of the flame may beimmersed in the composition. In light of the teachings herein, those ofskill in the art will be readily able to adapt a variety of conventionalapparatus and methods of flame suppression for use in the presentinvention.

Sterilization Methods

Many articles, devices and materials, particularly for use in themedical field, must be sterilized prior to use for the health and safetyreasons, such as the health and safety of patients and hospital staff.The present invention provides methods of sterilizing comprisingcontacting the articles, devices or material to be sterilized with acompound or composition of the present invention comprising a compoundof Formula I, preferably HFO-1234, and even more preferably HFO-1234ze,in combination with one or more sterilizing agents. While manysterilizing agents are known in the art and are considered to beadaptable for use in connection with the present invention, in certainpreferred embodiments sterilizing agent comprises ethylene oxide,formaldehyde, hydrogen peroxide, chlorine dioxide, ozone andcombinations of these. In certain embodiments, ethylene oxide is thepreferred sterilizing agent. Those skilled in the art, in view of theteachings contained herein, will be able to readily determine therelative proportions of sterilizing agent and the present compound(s) tobe used in connection with the present sterilizing compositions andmethods, and all such ranges are within the broad scope hereof. As isknown to those skilled in the art, certain sterilizing agents, such asethylene oxide, are relatively flammable components, and the compound(s)in accordance with the present invention are included in the presentcompositions in amounts effective, together with other componentspresent in the composition, to reduce the flammability of thesterilizing composition to acceptable levels.

The sterilization methods of the present invention may be either high orlow-temperature sterilization of the present invention involves the useof a compound or composition of the present invention at a temperatureof from about 250° F. to about 270° F., preferably in a substantiallysealed chamber. The process can be completed usually in less than about2 hours. However, some articles, such as plastic articles and electricalcomponents, cannot withstand such high temperatures and requirelow-temperature sterilization. In low temperature sterilization methods,the article to be sterilized is exposed to a fluid comprising acomposition of the present invention at a temperature of from about roomtemperature to about 200° F., more preferably at a temperature of fromabout room temperature to about 100° F.

The low-temperature sterilization of the present invention is preferablyat least a two-step process performed in a substantially sealed,preferably air tight, chamber. In the first step (the sterilizationstep), the articles having been cleaned and wrapped in gas permeablebags are placed in the chamber. Air is then evacuated from the chamberby pulling a vacuum and perhaps by displacing the air with steam. Incertain embodiments, it is preferable to inject steam into the chamberto achieve a relative humidity that ranges preferably from about 30% toabout 70%. Such humidities may maximize the sterilizing effectiveness ofthe sterilant, which is introduced into the chamber after the desiredrelative humidity is achieved. After a period of time sufficient for thesterilant to permeate the wrapping and reach the interstices of thearticle, the sterilant and steam are evacuated from the chamber.

In the preferred second step of the process (the aeration step), thearticles are aerated to remove sterilant residues. Removing suchresidues is particularly important in the case of toxic sterilants,although it is optional in those cases in which the substantiallynon-toxic compounds of the present invention are used. Typical aerationprocesses include air washes, continuous aeration, and a combination ofthe two. An air wash is a batch process and usually comprises evacuatingthe chamber for a relatively short period, for example, 12 minutes, andthen introducing air at atmospheric pressure or higher into the chamber.This cycle is repeated any number of times until the desired removal ofsterilant is achieved. Continuous aeration typically involvesintroducing air through an inlet at one side of the chamber and thendrawing it out through an outlet on the other side of the chamber byapplying a slight vacuum to the outlet. Frequently, the two approachesare combined. For example, a common approach involves performing airwashes and then an aeration cycle.

EXAMPLES

The following examples are provided for the purpose of illustrating thepresent invention but without limiting the scope thereof.

Example 1

The coefficient of performance (COP) is a universally accepted measureof refrigerant performance, especially useful in representing therelative thermodynamic efficiency of a refrigerant in a specific heatingor cooling cycle involving evaporation or condensation of therefrigerant. In refrigeration engineering, this term expresses the ratioof useful refrigeration to the energy applied by the compressor incompressing the vapor. The capacity of a refrigerant represents theamount of cooling or heating it provides and provides some measure ofthe capability of a compressor to pump quantities of heat for a givenvolumetric flow rate of refrigerant. In other words, given a specificcompressor, a refrigerant with a higher capacity will deliver morecooling or heating power. One means for estimating COP of a refrigerantat specific operating conditions is from the thermodynamic properties ofthe refrigerant using standard refrigeration cycle analysis techniques(see for example, R. C. Downing, FLUOROCARBON REFRIGERANTS HANDBOOK,Chapter 3, Prentice-Hall, 1988).

A refrigeration/air conditioning cycle system is provided where thecondenser temperature is about 150° F. and the evaporator temperature isabout −35° F. under nominally isentropic compression with a compressorinlet temperature of about 50° F. COP is determined for severalcompositions of the present invention over a range of condenser andevaporator temperatures and reported in Table I below, based uponHFC-134a having a COP value of 1.00, a capacity value of 1.00 and adischarge temperature of 175° F.

TABLE I DISCHARGE REFRIGERANT Relative TEMPERATURE COMPOSITION RelativeCOP CAPACITY ° F. HFO 1225ye 1.02 0.76 158 HFO trans-1234ze 1.04 0.70165 HFO cis-1234ze 1.13 0.36 155 HFO 1234yf 0.98 1.10 168

This example shows that certain of the preferred compounds for use withthe present compositions each have a better energy efficiency thanHFC-134a (1.02, 1.04 and 1.13 compared to 1.00) and the compressor usingthe present refrigerant compositions will produce discharge temperatures(158, 165 and 155 compared to 175), which is advantageous since suchresult will likely leading to reduced maintenance problems.

Example 2

The miscibility of HFO-1225ye and HFO-1234ze with various refrigerationlubricants is tested. The lubricants tested are mineral oil (C3), alkylbenzene (Zerol 150), ester oil (Mobil EAL 22 cc and Solest 120),polyalkylene glycol (PAG) oil (Goodwrench Refrigeration Oil for 134asystems), and a poly(alpha-olefin) oil (CP-6005-100). For eachrefrigerant/oil combination, three compositions are tested, namely 5, 20and 50 weight percent of lubricant, with the balance of each being thecompound of the present invention being tested

The lubricant compositions are placed in heavy-walled glass tubes. Thetubes are evacuated, the refrigerant compound in accordance with thepresent invention is added, and the tubes are then sealed. The tubes arethen put into an air bath environmental chamber, the temperature ofwhich is varied from about −50° C. to 70° C. At roughly 10° C.intervals, visual observations of the tube contents are made for theexistence of one or more liquid phases. In a case where more than oneliquid phase is observed, the mixture is reported to be immiscible. In acase where there is only one liquid phase observed, the mixture isreported to be miscible. In those cases where two liquid phases wereobserved, but with one of the liquid phases occupying only a very smallvolume, the mixture is reported to be partially miscible.

The polyalkylene glycol and ester oil lubricants were judged to bemiscible in all tested proportions over the entire temperature range,except that for the HFO-1225ye mixtures with polyalkylene glycol, therefrigerant mixture was found to be immiscible over the temperaturerange of −50° C. to −30° C. and to be partially miscible over from −20to 50° C. At 50 weight percent concentration of the PAG in refrigerantand at 60°, the refrigerant/PAG mixture was miscible. At 70° C., it wasmiscible from 5 weight percent lubricant in refrigerant to 50 weightpercent lubricant in refrigerant.

Example 3

The compatibility of the refrigerant compounds and compositions of thepresent invention with PAG lubricating oils while in contact with metalsused in refrigeration and air conditioning systems is tested at 350° C.,representing conditions much more severe than are found in manyrefrigeration and air conditioning applications.

Aluminum, copper and steel coupons are added to heavy walled glasstubes. Two grams of oil are added to the tubes. The tubes are thenevacuated and one gram of refrigerant is added. The tubes are put intoan oven at 350° F. for one week and visual observations are made. At theend of the exposure period, the tubes are removed.

This procedure was done for the following combinations of oil and thecompound of the present invention:

-   a) HFO-1234ze and GM Goodwrench PAG oil-   b) HFO1243 zf and GM Goodwrench oil PAG oil-   c) HFO-1234ze and MOPAR-56 PAG oil-   d) HFO-1243 zf and MOPAR-56 PAG oil-   e) HFO-1225 ye and MOPAR-56 PAG oil.

In all cases, there is minimal change in the appearance of the contentsof the tube. This indicates that the refrigerant compounds andcompositions of the present invention are stable in contact withaluminum, steel and copper found in refrigeration and air conditioningsystems, and the types of lubricating oils that are likely to beincluded in such compositions or used with such compositions in thesetypes of systems.

Comparative Example

Aluminum, copper and steel coupons are added to a heavy walled glasstube with mineral oil and CFC-12 and heated for one week at 350° C., asin Example 3. At the end of the exposure period, the tube is removed andvisual observations are made. The liquid contents are observed to turnblack, indicating there is severe decomposition of the contents of thetube.

CFC-12 and mineral oil have heretofore been the combination of choice inmany refrigerant systems and methods. Thus, the refrigerant compoundsand compositions of the present invention possess significantly betterstability with many commonly used lubricating oils than the widely usedprior art refrigerant-lubricating oil combination.

Example 4 Polyol Foam

This example illustrates the use of blowing agent in accordance with oneof the preferred embodiments of the present invention, namely the use ofHFO-1234ze, and the production of polyol foams in accordance with thepresent invention. The components of a polyol foam formulation areprepared in accordance with the following table:

PBW Polyol Component* Voranol 490 50 Voranol 391 50 Water 0.5 B-8462(surfactant) 2.0 Polycat 8 0.3 Polycat 41 3.0 HFO-1234ze 35 Total 140.8Isocyanate M-20S 123.8 Index 1.10 *Voranol 490 is a sucrose-based polyoland Voranol 391 is a toluene diamine based polyol, and each are from DowChemical. B-8462 is a surfactant available from Degussa-Goldschmidt.Polycat catalysts are tertiary amine based and are available from AirProducts. Isocyanate M-20S is a product of Bayer LLC.The foam is prepared by first mixing the ingredients thereof, butwithout the addition of blowing agent. Two Fisher-Porter tubes are eachfilled with about 52.6 grams of the polyol mixture (without blowingagent) and sealed and placed in a refrigerator to cool and form a slightvacuum. Using gas burets, about 17.4 grams of HFO-1234ze are added toeach tube, and the tubes are then placed in an ultrasound bath in warmwater and allowed to sit for 30 minutes. The solution produced is hazy,a vapor pressure measurement at room temperature indicates a vaporpressure of about 70 psig, indicating that the blowing agent is not insolution. The tubes are then placed in a freezer at 27° F. for 2 hours.The vapor pressure was again measured and found to be 14-psig. Theisocyanate mixture, about 87.9 grams, is placed into a metal containerand placed in a refrigerator and allowed to cool to about 50° F. Thepolyol tubes were then opened and weighed into a metal mixing container(about 100 grams of polyol blend are used). The isocyanate from thecooled metal container is then immediately poured into the polyol andmixed with an air mixer with double propellers at 3000 RPM's for 10seconds. The blend immediately begins to froth with the agitation and isthen poured into an 8×8×4 inch box and allowed to foam. Because of thefroth, a cream time cannot be measured. The foam has a 4-minute gel timeand a 5-minute tack free time. The foam is then allowed to cure for twodays at room temperature.The foam is then cut to samples suitable for measuring physicalproperties and is found to have a density of 2.14 pcf. K-factors aremeasured and found to be as follows:

Temperature K, BTU In/Ft² h ° F.  40° F. .1464  75° F. .1640 110° .1808

Example 5 Polystyrene Foam

This example illustrates the use of blowing agent in accordance with twopreferred embodiments of the present invention, namely the use ofHFO-1234ze and HFO-1234-yf, and the production of polystyrene foam. Atesting apparatus and protocol has been established as an aid todetermining whether a specific blowing agent and polymer are capable ofproducing a foam and the quality of the foam. Ground polymer (DowPolystyrene 685D) and blowing agent consisting essentially of HFO-1234zeare combined in a vessel. A sketch of the vessel is illustrated below.The vessel volume is 200 cm³ and it is made from two pipe flanges and asection of 2-inch diameter schedule 40 stainless steel pipe 4 incheslong (see Figure 1). The vessel is placed in an oven, with temperatureset at from about 190° F. to about 285° F., preferably for polystyreneat 265° F., and remains there until temperature equilibrium is reached.

The pressure in the vessel is then released, quickly producing a foamedpolymer. The blowing agent plasticizes the polymer as it dissolves intoit. The resulting density of the two foams thus produced using thismethod are given in Table 1 and graphed in Figure 1 as the density ofthe foams produced using trans-HFO-1234ze and HFO-1234yf. The data showthat foam polystyrene is obtainable in accordance with the presentinvention. The die temperature for R1234ze with polystyrene is about250° F.

TABLE 1 Dow polystyrene 685D Foam density (lb/ft³) T ° F.transHFO-1234ze HFO-1234yf 275 55.15 260 22.14 14.27 250  7.28 24.17 24016.93

What is claimed is:
 1. A propellant composition for expelling toward anarticle to be cleaned to remove a contaminant from the article at leastin part by contact with a material to be expelled, said compositionhaving a GWP of not greater than about 75 and comprising: (a) a solventto be carried to said article for cleaning of said article; and (b)liquefied gas propellant for expelling said solvent toward said article,said liquefied gas propellant comprising at least about 70% by weight of1,3,3,3-tetrafluoropropene, wherein at least about 97% of said1,3,3,3-tetrafluoropropene is trans-1,3,3,3-tetrafluoropropene(transHFO-1234ze), wherein the propellant and solvent are not the same,and wherein said propellant has no flammability in air as measuredaccording to ASTM-E681 and wherein said propellant has no substantialacute toxicity, as measured by inhalation exposure to mice and rats. 2.The composition of claim 1 wherein said propellant composition is anaerosol.
 3. The composition of claim 1 wherein said liquefied gaspropellant consists essentially of trans-1,3,3,3-tetrafluoropropene(trans-HFO-1234ze).
 4. The composition of claim 1 wherein said materialto be sprayed or expelled further comprises a cosmetic.
 5. Thecomposition of claim 4 wherein said cosmetic is selected from the groupconsisting of, perfumes, cleansers, polishing agents and combinations ofany two or more of these.
 6. The composition of claim 1 wherein saidmaterial to be sprayed or expelled further comprises a medicinalmaterial.
 7. The composition of claim 1 wherein said propellant has nosubstantial acute toxicity, as measured by inhalation exposure to miceand rats.
 8. A spray cleaner comprising the composition of claim
 1. 9. Alubricant comprising the composition of claim
 1. 10. A contact cleanercomprising the composition of claim
 1. 11. A duster comprising thecomposition of claim
 1. 12. A personal care product comprising thecomposition of claim
 1. 13. A cleaning composition for removing acontaminant from a surface or portion of an article comprising (a) atleast one liquefied gas propellant comprising at least about 70% byweight of 1,3,3,3-tetrafluoropropene, wherein at least about 97% of said1,3,3,3-tetrafluoropropene is trans-1,3,3,3-tetrafluoropropene(transHFO-1234ze), wherein said propellant has no flammability in air asmeasured according to ASTM-E681 and wherein said propellant has nosubstantial acute toxicity, as measured by inhalation exposure to miceand rats; and (b) at least a portion of said contaminant removed fromthe surface or portion of the article.
 14. The composition of claim 13wherein said liquefied gas propellant has a Global Warming Potential(GWP) of not greater than about
 1000. 15. The composition of claim 13 inthe form of an aerosol.
 16. The composition of claim 14 wherein saidcomposition further comprises a solvent carried by said at least oneliquefied gas propellant.
 17. The composition of claim 16 wherein saidat least one liquefied gas propellant consists essentially oftrans-1,3,3,3-tetrafluoropropene (transHFO-1234ze).
 18. The compositionof claim 16 wherein said liquefied gas propellant consists oftrans-1,3,3,3-tetrafluoropropene (transHFO-1234ze).
 19. The compositionof claim 13 further comprising CO₂.